Abstract
Bruxisim have been focused on as the mechanical forces that affected on the stomatognathic system; however the concept of habitual first stroke of mastication we proposed seemed to be more important than bruxism. In most of the clinical cases, the extent of power by the habitual first stroke of mastication is low level and may not be affected on the stomatognathic system, however once it fixed, it may become a destructive schock power to stomatognathic system, or once it accumulated over and over again, it may become accumulative and destructive power to stomatognathic system. In this report, we present the power by the habitual first stroke of mastication and give discussions on it.
